Pump assembly with one piece piston

ABSTRACT

An assembly including a pump attachment particularly adapted to form an nonaerosol pump sprayer, and a method of using the same. The apparatus desirably includes an attachment having a pump sprayer which is pressurized on the upstroke enabling the sprayer to be shipped and stored in a relaxed position. The attachment includes a body, a coupling, a shaft, a piston, an inlet valve and a biasing member. The body defines an elongate chamber having the first end, second end, and an interior wall extending between the first end and second end. The coupler is sized and shaped to secure the body to the neck of a container. The shaft extends through the opening in the first end of the chamber and defines an internal flow channel. The piston is reciprocally mounted within the chamber and includes an inner annular surface surrounding the shaft and an outer annular surface sized and shaped to form a sealing engagement with the interior wall of the body. The attachment defines a sealing surface substantially fixed with respect to the piston and a second sealing surface substantially fixed with respect to the shaft. The first sealing surface and the second sealing surface having the first position wherein the first sealing surface and the second sealing surface cooperate to prevent the flow of liquid between the piston and the shaft. The first sealing surface and the second sealing surface also has a second position wherein the first sealing surface and the second sealing surface permit the flow of liquid between the piston and the shaft. The piston is formed from a single piece said piston and defines an inner annular surface surrounding the shaft and an upper outer annular surface sized and shaped to form a sealing engagement with said interior wall of the body and a lower outer annular surface sized and shaped to form a sealing engagement with the interior wall of said body.

RELATED APPLICATIONS

[0001] This application is a continuation of U.S. patent applicationSer. No. 08/580,682, filed May 30, 2000, which is a continuation of U.S.patent application Ser. No. 08/949,837, filed Oct. 14, 1997, now issuedas U.S. Pat. No. 6,089,414, which is a continuation-in-part of U.S.patent application Ser. No. 08/812,790, filed Mar. 6, 1997, now issuedas U.S. Pat. No. 5,816,447.

FIELD OF THE INVENTION

[0002] This invention relates to pumps and, in particular, to nonaerosolpump sprayers.

BACKGROUND AND SUMMARY OF THE INVENTION

[0003] Noncontainer pressurizing pump sprayers commonly utilize anintegral cylinder and plunger arrangement to generate pressure to expelliquid, such as insecticide and fertilizer from a container.Noncontainer pressurizing pump sprayers are desirable in that they donot utilize pressurized containers which must be handled carefully andat controlled temperatures to avoid the risk of explosion. Noncontainerpressurizing pump sprayers have a number of other advantages, includingnot using propellants which destroy the ozone and being relativelyinexpensive.

[0004] There are two common varieties of noncontainer pressurizing pumpsprayers: pump sprayers that are pressurized on the upstroke and pumpsprayers that are pressurized on the downstroke. Pump sprayers that arepressurized on the downstroke typically utilize a return spring whichbiases the plunger upward after the pressurization stroke. Thesesprayers suffer from the drawback that it is often undesirable to storeor ship the pump sprayer with the plunger in the up position.Accordingly, the pump sprayer is generally shipped and stored with thereturn spring in a compressed position, causing the spring to fatigueand begin to wear out prematurely. Likewise, in the event of theinadvertent release of the return spring, the plunger cannot bedepressed without pressurizing the fluid in the container. In the caseof insecticide or other toxic chemicals, this is often undesirable.

[0005] While pump sprayers that are pressurized by pulling the plungerupward have the advantage of not having the plunger being forced outwardinadvertently, they too, suffer from a number of drawbacks. For example,once the plunger is drawn upward, it is generally not possible to lowerthe plunger without discharging fluid. As drawing the plunger upwardcreates a relatively large volume of pressurized liquid, this eitherrequires that a relatively large amount of fluid be wasted or the devicebe stored with the plunger extending outward.

[0006] U.S. Pat. No. 4,174,055, to Capra, et al., discloses analternative dispenser. The disclosed dispenser incorporates a plungerwhich pressurizes the fluid on the upstroke, but also is provided with aseparate return spring and collar for purposes of lowering the plungerhandle independently of the main plunger piston. While this arrangementhas advantages, it is more complicated and expensive than other pumpsprayer arrangements. Further, while the system provides for slowbleeding off of pressure, the sprayer remains in a pressurized state forsome time. Significantly, this substantially increases the risk ofinadvertent discharge of chemicals by adults or children who may comeinto contact with the device.

[0007] The present invention includes an apparatus and pump attachmentparticularly adapted to form a noncontainer pressurizing pump sprayerwhich overcomes the drawbacks of the prior art. The apparatus desirablyincludes an attachment having a pump sprayer which is pressurized on theupstroke, enabling the sprayer to be shipped and stored in a relaxedposition. Importantly, however, the plunger is adapted to permit theplunger to be quickly and easily lowered and the apparatus depressurizedwithout discharging fluid. Significantly, these advantages are providedin a apparatus which is particularly adapted to be inexpensivelymanufactured and includes few moving parts, to enhance reliability.

[0008] One aspect of the invention is a pump attachment for a containerdefining a neck including a body, a coupling, a shaft, a piston, aninlet valve and a biasing member. The body defines an elongate chamberhaving a first end, a second end, and an interior wall extending betweenthe first end and the second end. The coupler is sized and shaped tosecure the body to the neck of a container. The shaft extends throughthe opening in the first end of the chamber and defines an internal flowchannel. The piston is reciprocally mounted within the chamber anddefines an inner annular surface surrounding the shaft and an outerannular surface sized and shaped to form a sealing engagement with theinterior wall of the body. The piston separates the chamber into anupper portion above the piston and lower portion below the piston. Theinlet valve is at the second end of the body and is configured to permitthe flow of fluid into the chamber and restrict the flow of fluid out ofthe chamber. The biasing member is positioned between the piston and thefirst end of the chamber.

[0009] The attachment defines a first sealing surface substantiallyfixed with respect to the piston and a second sealing surfacesubstantially fixed with respect to the shaft. The first sealing surfaceand the second sealing surface have a first position wherein the firstsealing surface and the second sealing surface cooperate to prevent theflow of liquid between the piston and the shaft. The first sealingsurface and the second sealing surface have a second position whereinthe first sealing surface and the second sealing surface permit the flowof liquid between the piston and the shaft.

[0010] Advantageously, the shaft includes an outwardly extending surfacewhich prevents the piston from sliding beyond the one end of the shaft.Likewise, the attachment desirably includes a first O-ring mounted onthe shaft which defines the second sealing surface and an inwardlytapered seat which defines the first sealing surface. Alternatively, thepiston may comprise one piece and define an upper outer annular surfacesized and shaped to form a sealing engagement with the interior wall ofthe body and a lower outer annular surface sized and shaped to form asealing engagement with the interior wall of the body. Desirably, theupper outer annular surface is defined by an upper lip adapted to flexoutward in response to downward pressure and the lower outer annularsurface is defined by a lower lip adapted to flex outward in response toupward pressure.

[0011] The attachment may also include a spray nozzle communicating withthe internal flow channel and an actuator for selectively preventing theflow of a fluid through the spray nozzle.

[0012] The attachment desirably includes a handle secured to the shaftand a latch movable between a first location wherein the latch generallyprevents the shaft from being drawn through the first end of the bodyand the second location wherein the latch generally permits the shaft tobe drawn through the first end of the body. Alternatively, the handle isintegrally formed with the shaft so as to form a single piece plunger,thereby eliminating a potential leak point.

[0013] Another aspect of the invention is an apparatus including acontainer defining a neck and an attachment. The attachment includes abody, a coupler, a shaft, a piston, an inlet valve, and a biasingmember. The body defines an elongate chamber having a first end, asecond end and an interior wall extending between the first end and thesecond end. The coupler is sized and shaped to secure the body to theneck of the container. The shaft extends through an opening in the firstend of the chamber and defines an internal flow channel. The piston isreciprocally mounted within the chamber and defines an inner annularsurface surrounding the shaft and an outer annular surface sized andshaped to form a sealing engagement with the interior wall of the body.The piston separates the chamber into an upper portion above the pistonand a lower portion below the piston. The inlet valve at the second endof the body is configured to permit the flow of fluid into the chamberand restrict the flow of fluid out of the chamber. The biasing member ispositioned between the piston and the first end of the chamber.

[0014] The attachment includes a first sealing surface substantiallyfixed with respect to the piston and a second sealing surfacesubstantially fixed with respect to the shaft. The first sealing surfaceand the second sealing surface have a first position wherein the firstsealing surface and the second sealing surface cooperate to prevent theflow of liquid between the piston and the shaft. The first sealingsurface and the second sealing surface have a second position whereinthe first sealing surface and the second sealing surface permit the flowof liquid between the piston and the shaft.

[0015] Another aspect of the invention is a method of arming anddisarming a spray apparatus, including a container containing fluid andan attachment mounted thereto having a body defining an elongatechamber, a shaft extending through an opening in the chamber, the shaftdefining an internal flow channel, a piston reciprocating mounted in thechamber, a check valve and a biasing member, including (1) moving theshaft in a first direction relative to the body, thereby moving thepiston in the direction and drawing fluid from the container into thechamber through the check valve and compressing the biasing member; (2)permitting the biasing member to force the piston against the fluid inthe chamber in a second direction pressurizing the fluid; (3) releasingliquid from the chamber through the internal flow channel in the shaft;and (4) moving the shaft in a second direction relative to the body andthe piston to release a seal between the piston and the shaft, therebypermitting the flow of fluid between the piston and the shaftdepressurizing the fluid.

[0016] Another aspect of the invention is a spray nozzle including agrip, a nose having a spray end, a valve housing, a valve and anactuator. The actuator is connected to the valve. The valve housing ismounted within either the grip or the nose. The valve housing defines aclosed end, an inlet port and an outlet port. The valve is mountedwithin the housing and has a flow portion, a first seal on one side ofthe flow portion and the second seal on the other side of the flowportion. The valve has a first position wherein the valve prevents theflow of fluid between the inlet port and the outlet port, and a secondposition wherein the valve permits the flow of fluid between the inletport and the outlet port. The first seal and the second seal arepositioned to one side of the inlet port when the valve is in the firstposition. The first seal and the second seal are positioned on oppositesides of the inlet port and the outlet port when the valve is in thesecond position. Desirably, the valve comprises a one-piece shaft memberand no more than two O-rings.

[0017] Yet another aspect of the invention is an assembly for acontainer. The assembly includes a grip, a coupler sized and shaped tosecure the grip to the neck of a container, a plug and an adaptor. Thegrip includes a handle portion and a stem portion. The handle portionhas a first inner wall defining a first flow channel having a firstoutlet. The stem portion defines a second inner wall defining a secondflow channel having a second outlet. The first flow channel and thesecond flow channel intersect at the outlet of the second flow channel.The plug is mounted within the first flow channel and has a firstposition wherein the plug prevents fluid flow from the second outlet tothe first outlet, and a second position wherein the plug permits fluidflow from the second outlet to the first outlet. The adaptor has aninner section sized and shaped to be inserted into the first flowchannel to move the plug between the first position and the secondposition. Desirably, the plug further includes an inner flow channelthrough which fluid is flowable when the plug is in the second position.The adaptor preferably comprises a connector for securing a piece oftubing to the handle portion of the grip.

[0018] Finally, yet another aspect of the invention is an assemblyincluding a container and a sprayer. The container defines a wall, afirst stud and a second stud. Each of the first stud and the second studinclude a head portion and a stem portion. The sprayer has a spray endand a wall. The wall defines a first opening and a second opening. Eachof the openings includes a first portion wider than the stem portion andnarrower than the head portion, and a second portion wider than the headportion so that the head portion of the stud is insertable therethrough.Advantageously, the container includes a seam and the first stud and thesecond stud intersect the seam. Preferably, the second portion of theopening is positioned closer to the spray end than the first portion ofthe opening. Desirably, for each of the first stud and second stud, thehead portion overhangs the stem portion a first overhang distance on afirst side, and a second overhang distance on a second side. At leastone of the first overhang distance and the second overhang distance isadvantageously at least 0.015 of an inch.

BRIEF DESCRIPTION OF THE DRAWINGS

[0019] These and other aspects of the invention will now be discussed inconnection with the accompanying drawings, which form a part hereof.

[0020]FIG. 1 is a vertical sectional view of an apparatus including apump attachment, in accordance with a preferred embodiment of theinvention, showing the parts in their normal at-rest position.

[0021]FIG. 1a is an enlarged sectional view of the area with the circle1 a-1 a of FIG. 1.

[0022]FIG. 1b is an enlarged sectional view of the area within thecircle 1 b-1 b of FIG. 1a, illustrating an open vent passage.

[0023]FIG. 1c is an enlarged sectional view similar to FIG. 1b, butillustrating a closed passage.

[0024]FIG. 1d is an enlarged sectional view similar to FIG. 1a, butshowing the handle plug used during shipping.

[0025]FIG. 1e is an enlarged view of a locking ring used by the adaptor.

[0026]FIG. 2 is a vertical sectional view of the device of FIG. 1,showing the actuator moved to an upwardly or outwardly telescopedposition relative the container in order to move the piston in theaccumulating chamber or reservoir to compress the biasing member andpressurize fluid within the chamber.

[0027]FIG. 3 is a sectional view taken along 3-3 of FIG. 2, illustratingthe latch in an unlocked position.

[0028]FIG. 4 is a sectional view similar to FIG. 3, but illustrating thelatch in a locked position.

[0029]FIG. 5 is a partial sectional view illustrating the pumpattachment in a fully pressurized position.

[0030]FIG. 6 is a partial sectional view illustrating the release ofpressure in the chamber by means of an external downward force on thehandle.

[0031]FIG. 6a is an enlarged sectional view of the area 6 a-6 a of FIG.6 illustrating the flow of fluid between the outer surface of the shaftand the inner annular surface of the piston.

[0032]FIG. 7 illustrates the pump attachment in its fully locked andretracted position quickly depressurizing through the flow of fluidbetween the shaft and the piston.

[0033]FIG. 8 is a view similar to FIG. 6a illustrating a firstalternative piston design.

[0034]FIG. 9 is an enlarged sectional view of a second alternativepiston design.

[0035]FIG. 9a is a top plan view of the piston of FIG. 9.

[0036]FIG. 9b is a bottom plan view of the piston of FIG. 10.

[0037]FIG. 10 is an enlarged sectional view of a third alternativepiston design.

[0038]FIG. 11 is a sectional view of an alternative handle and shaftdesign, where the handle and shaft are integrally formed.

[0039]FIG. 12 is a perspective view of a prior art container and sprayerassembly.

[0040]FIG. 13 is an enlarged view of the sprayer of the assembly of FIG.12.

[0041]FIG. 14 is a sectional view illustrating the connection betweenthe sprayer and container of FIG. 12, when the sprayer is mounted on thecontainer.

[0042]FIG. 15 is a front elevational view of a preferred apparatusincluding a cutout illustrating the manner in which the sprayer ismounted on the container.

[0043]FIG. 16 is a left side view of the container of FIG. 16, withoutthe spray attachment mounted thereon.

[0044]FIG. 17 is an enlarged schematic sectional view illustrating themethod of molding the container of FIG. 15, including a bayonetattachment.

[0045]FIG. 18 is a top plan view of an alternative sprayer.

[0046]FIG. 19 is a front elevational view of the sprayer of FIG. 18.

[0047]FIG. 20 is a sectional view of the sprayer of FIG. 18 taken along20-20.

[0048]FIG. 21 is a sectional view of the sprayer of FIG. 19 taken along21-21.

[0049]FIG. 22 is an enlarged partial sectional view of the valvemechanism of a sprayer in a closed position.

[0050]FIG. 23 is a partial sectional view of the valve mechanism in anopen position.

[0051]FIG. 24 is a partial sectional view of an alternative valvemechanism in a closed position.

[0052]FIG. 25 is an enlarged partial sectional view of the sprayer ofFIG. 24 in an open position.

[0053]FIG. 25a is an enlarged sectional view along 25 a-25 a of FIG. 25.

[0054]FIG. 26 is an enlarged partial sectional view illustrating asecond alternative embodiment of the valve mechanism of a sprayer in aclosed position.

[0055]FIG. 27 is a partial sectional view of the valve of FIG. 26 in anopen position.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0056] Referring now to FIG. 1, an assembly 10 will now be described.The assembly 10 includes a container 20 and pump attachment 30. Thecontainer 20 is illustrated partially filled with fluid 260. Thecontainer 20 defines an internal space or reservoir 22 and a neck 24which defines an opening or port 26. The neck 24 desirably defines aseries of external threads 28.

[0057] The attachment 30 includes a body 40, which is secured on thecontainer 20 by means of a coupler 70. The attachment further includes ashaft 110 which is connected to a piston 130. A handle 190 is mounted onthe shaft 110. A wand or spray nozzle 220 is connected to the handle 190by tubing 222. Advantageously, the nozzle 220 includes a release valve,which controls the flow of fluid through the spray nozzle 220 and anactuator 240 for controlling the release valve.

[0058] Referring to FIG. 5, the body 40 of the attachment 30 will now bedescribed in detail. The body 40 defines an internal chamber 42. Thebody 40 includes first or upper end 44, a second or lower end 46 and acylindrical internal wall 48. The upper end 44 of the body 40 includesan outwardly tapering portion 50 and an upper cylindrical flange 52,provided with internal threads 54. The lower end 46 of the body 40 isprovided with an annular overhanging lip 56 defining a series ofopenings 58 and a depending flange 60 extending downward from theannular lip 56 surrounding the opening 58.

[0059] Referring to FIGS. 3-4 and 5, the coupler 70 includes adisk-shaped base 72 which partially defines a central aperture 74. Acoupler 70 includes a pair of depending and concentric annular lips. Thefirst or inner annular lip 76 likewise partially defines the aperture74. The second or outer annular lip 78 is spaced from and surrounds theinner annular lip 76.

[0060] The inner annular lip 76 defines an overhanging flange 82 and adepending ridge 84. The inner lip 76 and the overhanging flange 82cooperate to define a handle seat. The overhanging flange 82 anddepending ridge 84 cooperate to define an inner O-ring seat. The firstannular lip 76 and the depending ridge 84 likewise form an outer annularspring groove 88. The inner annular lip 76, the base 72 and outerannular lip 78 cooperate to define a first annular channel 90. Whichdefines a seat which receives an O-ring 91. The outer annular lip 78 isprovided with internal threads 96.

[0061] Alternatively, the flange 52 of the body 40 could be providedwith external threads and the lip 76 of the coupler 70 with internalthreads. This arrangement would facilitate tooling to form the body.

[0062] The shaft 110 has a first or upper end 112 and a second or lowerend 114. The upper end is provided with external threads 116. The lowerend 114 of the shaft 110 advantageously includes a radially outwardextending portion 118. The shaft includes an internal wall 120 whichdefines an internal flow channel 122 having a lower inlet end 124 and anupper outlet end 126.

[0063] Referring to FIGS. 6 and 6a, the piston 130 is mounted around theshaft 110. The piston includes a body 132 having a top 134 and bottom136. The piston defines an inner annular surface 138, which defines aninternal channel 140. The inner annular surface 138 desirably defines atapering portion 142. The piston 130 desirably additionally includes aseries of radially extending locating ribs which define a series ofupper surfaces 144. These surfaces 144 cooperate to define an outerannular groove 146 for receiving the biasing member 180.

[0064] Referring to FIGS. 5 and 6, the piston 130 divides the internalchamber 42 of the body 40 of the attachment into a first or upperportion 150 and a second or lower portion 152. Mounted within theopening 58 defined by the overhanging lip 56 of the lower end 46 of thebody 40 is the inlet or check valve 160. The check valve 160 permits theflow of fluid into the internal chamber 42 of the body 40 of theattachment, while preventing the flow of fluid out of the internalchamber 42. Advantageously, the check valve 160 is provided with anupper nipple 162 which mates with the inlet 124 of the shaft. The lowernipple 166 secures the check valve 160 in place. Likewise, the checkvalve is provided with a lower nipple 166 depending from the overhanginglip 56 of the lower end 46 of the body 40. The check valve defines acentral flow channel 168.

[0065] The biasing member 180 has a first or upper end 182 which isseated in the outer annular spring groove 88 of the coupler and a secondend 184 which is seated in the annular groove 146 in the top of 134 ofthe piston 130.

[0066] Referring to FIG. 5, the handle 190 is mounted on the upper end112 of the shaft 110. The handle includes a vertical stem 192 and a gripor horizontal portion 194. The horizontal portion is desirablyintegrally formed with an upper end 196 of the stem 192 and the lowerend 198 of the stem 192 is desirably secured to the upper end 112 of theshaft 110. The stem desirably defines an internal flow channel 200. Thelower end 198 of the stem 192 desirably defines a larger mouth portion202 which defines internal threads 204 with the external threads of 116on the upper end 112 of the shaft 110. The horizontal portion 194desirably likewise defines an internal flow channel 206 whichcommunicates with the internal flow channel 200 of the stem 192, andincludes a closed end 208 and an open end 210.

[0067] Referring to FIGS. 1 and 1a-1 d, the attachment of the tubing 222to the horizontal portion 194 of the handle 190 will now be described.To ensure a fluid-tight seal, the tubing 222 is locked to a connector or300 and the adaptor 300 is locked to the horizontal portion 194 of thehandle 190. As seen in FIG. 1a, the adaptor 300 has a disc-shaped outersection 302, a cylindrical intermediate section 304 and a smallerdiameter cylindrical inner section 306. A cylindrical wall 307 definesan interior flow channel 309 running the length of the adaptor. Theintermediate section 304 includes an enlarged annular stop 308 proximateto the inner section 306. The inner section 306 includes an annularlocking flange 310 which mates with a corresponding annular detent inthe horizontal portion 194 of the handle 190. The inner section 306further comprises a first sealing ring 312 and a second sealing ring 314spaced inward from the locking flange and sized to form a fluid-tightseal with the wall defining the internal flow channel 206 of thehorizontal portion 194 of the handle 190. The outer section 302 definesa pocket 316 for receiving a locking ring 318. As best seen in FIG. 1e,the locking ring 318 defines a plurality of gripping edges or corners320, which are adapted to apply pressure against the outer surface ofthe tubing 222 and prevent it from being inadvertently pulled from theadaptor 300. FIG. 11 shows an integrally formed one-piece handle andshaft or plunger 424 which may be used in place of the two-piece handleand shaft described above. The integral plunger 424 would eliminate apossible leak point between the handle and shaft. The plunger 424includes a shaft portion 426 and a handle portion 428 which are joinedat a stop collar 430. The handle portion 428 includes as vertical stemsection 432 and a horizontal grip section 434. The shaft portion 426 ofthe plunger 424 includes an internal wall 436, which mates with a plug438. The plug includes an insert portion 440 which is received withinthe shaft portion 426 and an exterior portion 442 which protrudesoutside of the shaft portion 426. The insert portion 440 includes aradially extending annular ridge 444 which mates with an annular recess446 in the internal wall 436 of the shaft portion 426.

[0068] Alternatively, it may be desirable to provide external threads onthe distal end of the shaft portion 426 and an alternative plug withinternal threads to mate therewith. This would eliminate the need forthe annular recess 446 in the inner surface of the shaft which couldfacilitate the molding of the plunger 424.

[0069] Illustrated in FIG. 11a is an alternative adaptor or connector850 secured within the handle portion 428 of the one piece plunger 424.The connector 850 has a larger diameter head portion and a smallerdiameter body portion. Importantly, the connector 850 avoids the use ofa locking ring. The elimination of the locking ring facilitates thequick and easy attachment of the connector 850 to the plunger 424, whilean added O-ring 852 adjacent to the inner end of the head portionprevents leaks.

[0070]FIG. 11a also illustrates an alternative plug 860 for blocking theflow channel through the stem section 432 of the handle portion 428. Theplug 860 is similar to the plug 344, with the exception that the plug issolid and does not incorporate a second sealing flange. The solid plughas greater strength and the elimination of the second sealing flangereduces binding.

[0071] To ensure proper operation of the assembly 10, the assemblyincludes a number of additional sealing members, which will now bedescribed. A first seal or O-ring 252 is mounted at the upper end 44 ofthe attachment 30 within the inner O-ring seat defined by the firstannular lip 76 and overhanging flange 82 out of the coupler 70. Thefirst O-ring 252 is secured within the seat by means of an annularretaining clip 254 which desirably surrounds the depending ridge 84.Referring to FIGS. 6 and 6a, a second seal or O-ring 256 surrounds thesecond end 114 of the shaft 110 and desirably abuts against the radiallyoutward extending portion 118 of the shaft 110. To ensure that thepiston 130 forms a sealing engagement with the internal wall 48 of thebody 40 of the attachment 30, the piston 130 is desirably provided witha first and a second sealing gasket or cup seals, 258 and 260,respectively. Specifically, the body 132 of the piston 130 desirablydefines an annular space between the bottom 136 of the piston and theportion of the body 132 which defines the outer annular surface 144 andthe gaskets 258 and 260 are resiliently secured to the body 132 fillingthe space. The gaskets 258 and 260 ensure that the piston 130 forms afluid-tight seal with the internal wall 48 of the body 40 and preventflow between the gaskets 258 and the external wall of the piston body.

[0072]FIG. 8 shows an alternative piston design which may be desirableto avoid the need for relatively expensive cup seals. Specifically, thepiston 400 defines an outer generally cylindrical surface 402 which isbisected by an annular triangular groove 404 which receives a sealingmember or O-ring 406. The O-ring 406 ensures a fluid-tight seal betweenthe piston 400 and the internal wall of the body of the attachment.

[0073] Referring now to FIGS. 9, 9A and 9B, there is shown a secondalternative piston 450 which may be desirable to avoid the need forseparate seals. The piston 450 defines an outer cylindrical surface 452,an upper annular lip 454, and a lower annular lip 456. Advantageously,use of this piston 450 avoids the need for a separate O-ring seal andreduces the stacking of tolerances. Specifically, in designs usingseparate O-rings, it is required to maintain the tolerance of the innerwall of the body, the external cylindrical wall of the piston, and theO-ring itself. By eliminating the use of the separate O-rings, it isonly necessary to maintain the tolerances of the piston 450 and theinner wall of the body 40.

[0074]FIG. 10 shows a third alternative piston design 470. The piston470 defines an outer cylindrical surface 472, an intermediate recess474, an upper annular foot 476 and a lower annular foot 478. Other thanthe intermediate recess, the piston 470 is similar to the piston 450.The intermediate recess 474 has the advantage of providing a piston withuniform wall thickness and a piston which requires less material tomanufacture.

[0075] The assembly 10 is desirably provided with a mechanism forlocking the handle in a fully retracted position. Referring to FIGS. 1,3 and 4, the coupler 70 desirably defines a pair of parallel L-shapedoverhanging flanges 270. The flanges 270 are sized and shaped to permita locking plate 272 to slide snugly between the flanges 270. The lockingplate includes a first end 274 and a second end 276. The first end 274defines a first grip portion 278 and the second end 276 defines a secondgrip portion 280. Desirably, the locking plate defines a vent passage282 which cooperates with a corresponding vent opening 322 in the base72 of the coupler 70, when the locking plate is in its unlockedposition. Surrounding the top of the vent opening 322 is a sealingmember 324, such as an O-ring to prevent leakage of fluid when thelocking plate 272 is in its locked position, as shown in FIG. 1c.

[0076] The locking plate 272 defines an aperture 284 including a firstsmaller portion 286 defined by first edge 288 sized and shaped to snuglyreceive the portion of the stem 192 of the handle 190 above the largermouth portion 202. The aperture 284 further includes a larger secondportion 290 defined by a second edge 292 which is sized and shaped topermit the free movement of the larger mouth portion 202 of the stem 192of the handle 190 therethrough.

[0077] Referring to FIG. 3, the base 72 of the coupler 70 desirablydefines a raised dimple 325 positioned to abut the outer edge of thelocking plate 272 to keep the locking plate from sliding when thelocking plate 272 is in the open position. Advantageously, the lockingplate 272 is provided with a mating detent 326 to receive and retain thedimple 325 when the locking plate is in the closed position shown inFIG. 4.

[0078] Referring to FIGS. 18-21, a sprayer 500 for use in connectionwith assembly will now be described in detail.

[0079] The sprayer 500 includes a generally cylindrical grip 502, anarrow nose 504 having a generally plus-shaped cross-section and a sprayend 506. Advantageously, a separate spray piece 508 is provided topermit the spray to be adjusted.

[0080] The sprayer 500 includes an actuator 510 surrounded by a thumbrest 512 (FIG. 19). As best seen in FIG. 21, the grip 502 of the sprayer500 defines a pair of openings 514. Each opening is defined by a firstgenerally c-shaped wall defining a larger portion of the opening 518 anda second c-shaped wall 520 defining a smaller portion of the opening522.

[0081] The grip 502 also defines a slot 530 for receiving the connector850. The connector 532 is connected by a length of tubing 534 to a valvehousing 550. Advantageously, the tubing 534 is wrapped around a valvehousing to prevent any pulling on the tubing 534 from disconnecting thelink tubing 534 from the valve housing 550.

[0082] As best seen in FIGS. 22-23, the valve housing 550 includes aninlet portion 552 including a first wall 554 which defines an inletchannel 556 and a first port 558. The valve body also includes an outletportion 562 which includes a second wall 564 which defines an outletchannel 566 which in turn defines a second port 568. The inlet portion552 and the outlet portion 562 are connected by an intermediate portion572. The intermediate portion 572 includes a third wall 574 whichdefines a connecting chamber 576. The third wall further defines abottom vent port 578. The inlet portion 552 defines a pocket 582 forreceiving a locking ring 584 to secure the tubing 534 within the inletchannel 556.

[0083] The actuator 510 is connected to and is integrally formed withthe valve. The valve has a valve shaft 588 including a narrow portion590. A first recess 592 is positioned above the narrow portion 590 andreceives a first O-ring 594. A second recess 596 is positioned below thenarrow portion 590 and receives a second O-ring 598. A third recess 600is positioned below the second recess and receives a third O-ring 602.

[0084]FIG. 22 shows the valve in a off position, with flow entering theinlet portion 552 and seeking to flow into the intermediate portion 572through the first port 558. Flow, however, is blocked by the secondO-ring 598 positioned just above the first port 558 and the third O-ring602 positioned just below the first port 558.

[0085]FIG. 23 illustrates the valve in a flow through position where thevalve shaft 588 has been depressed so that both the second O-ring andthe third O-ring are positioned below the first port 558. As such, flowis able to pass through the first port 558 around the narrow portion 590of the valve shaft 588 through the second port 568 and through theoutlet portion 562 of the valve housing 550. Advantageously, the lowervent port 578 prevents fluids from being trapped in the valve body,which otherwise might prevent operation of the valve.

[0086]FIG. 24 illustrates a first alternative valve assembly including avalve housing 610 defining an inlet portion 612 having a first wall 614which defines an inlet channel 616 and a first port 618. The valvehousing 610 further includes an outlet portion 622 including a secondwall 624 which defines an outlet channel 626 and a second port 628. Thevalve housing likewise includes an intermediate portion 632 between theinlet portion 612 and the outlet portion 622. The intermediate portion632 defines a third wall 634 which defines a connecting chamber 636 anda closed end 640. The actuator includes a valve shaft 644 having anarrow portion 646 and a first recess 648 for receiving a first O-ring650. The valve shaft 644 likewise defines a second recess 652 forreceiving a second O-ring 654. FIG. 24 illustrates the valve in a closedposition. Flow is prevented from flowing through the assembly by thethird wall 634 of the connecting chamber and the second O-ring 654.

[0087]FIGS. 25 and 25A illustrate the valve assembly in an openposition, with the valve depressed. In this position, the valve shaft644 is depressed so that a portion of the narrow portion 646 of theshaft is aligned with the first port 618 so that flow through the firstport 618 around a narrow portion 646 of the valve shaft 644 and throughthe second port 628 is permitted. Importantly, fluid is not trappedwithin the closed end 640 of the valve body 610 because the first port618 is sized, shaped, and positioned such that in the on position, fluidis permitted to flow not only through the inlet portion 612 above thesecond O-ring 654 but also from the closed end 640 of the valve body 610beneath the second O-ring and back into the inlet portion 612 of thevalve body. This arrangement prevents fluid from dripping out of thevalve body, while at the same time preventing fluid trapped within theclosed end of the valve body 610 from preventing proper operation of thevalve.

[0088]FIG. 26 shows a second alternative valve assembly including analternative valve housing 660. The valve housing 660 includes an inletportion 662 having a first wall 664 which defines an inlet channel 666and a first port 668. The valve housing 660 also defines an outletportion 672 having a second wall 674 which defines an outlet channel 676and a second port 678. Positioned between the inlet portion 662 and theoutlet portion 672, is an intermediate portion 682. The intermediateportion 682 has a third wall 684 which includes an upper portion 686 anda lower portion 688. The third wall defines a connecting chamber 690.

[0089] The valve shaft 700 includes an outer section 702 connected tothe actuator, a narrow intersection 704 and an intermediate section 706.The outer section 702 has a larger diameter than the intermediatesection 706 and the intermediate section 706 has a larger diameter thanthe inner section 704. A first sealing flange 710 is positioned betweenthe outer section 702 and the intermediate section 706 of the valveshaft. A second sealing flange 708 is positioned at the distal end ofthe inner section 704 opposite the outer section 702. Advantageously,the first sealing flange 710 cooperates with the upper portion 686 ofthe third wall 684 to prevent fluid from passing out of the valve body660. Similarly, the second sealing flange 708 cooperates with the lowerportion 688 of the third wall 684 to prevent fluid from passingtherebetween. FIG. 26 illustrates the second alternative embodiment ofthe valve in a closed position. In this position, flow is permittedthrough the inlet portion 662 and into the connecting chamber 690, butis prevented from flowing through the second port 678 by the secondsealing flange 710. FIG. 27 illustrates the second alternative valve inan open position. In this position, the actuator shaft 700 is depressedand fluid flows through the inlet channel 666 through the first port 668around the inner section 704 of the actuator shaft 700, through thesecond port 678 and through the outlet channel 676.

[0090] The operation of the apparatus will now be described.

[0091] Referring to FIG. 1 and 1 d, during storage or shipment, theshaft 110 is secured in its fully retracted position, with the shoulderor mouth portion 202 of the handle 190 being retained in position by thelocking plate 272. During shipment, the tubing 222 connecting the spraynozzle 222 to the handle 190 may be secured in a hollow portion of thespray nozzle 220. The nozzle 220 is desirably provided with a pair ofopenings 340 for receiving and retaining a pair of mating studs 342projecting from the side of the container 20.

[0092]FIG. 15 shows an alternative assembly 720 including a container730, a pump attachment 740 and a sprayer 750. The container includes apair of studs 752 positioned on the back wall of the container. Each ofstuds is identically shaped. The assembly 720 is generally the same asthe assembly 10, with the exception of the shape of the studs. As shownin FIG. 15, the sprayer 750 is mounted on the container 730 by means ofcooperation of the studs 752 and the wall of the sprayer defining thebayonet openings. As best seen in FIGS. 15 and 17, the studs 752 includea stem portion 754 and a taller and wider head portion 756. The headportion defines a first overhang portion 758 which extends beyond theedge of the stem portion 754 a distance D1. Similarly, the head portion756 defines a second overhang 760 extending beyond the opposite side ofthe stem portion 754 a distance D2. Advantageously, the distances D1 andD2 are at least 0.015 inches, and are preferably 0.025 inches.

[0093] This mounting arrangement is superior to the mountingarrangements of prior art in that it facilitates the manufacture of asimple, inexpensive and secure mounting means for the sprayer.

[0094] FIGS. 12-14 illustrate a prior art assembly 770 including acontainer 772, connected by tubing 774 to a sprayer 776. The sprayerincludes a nozzle 778, a trigger 780 and a handle 782. The container 772defines a recess 784 and a sidewall for receiving the nozzle 778,trigger 780 and handle 782 of the sprayer 776. The container 772 definesa pair of generally rectangular raised protrusions 786 which extendoutward from the side wall of the container 772. As best seen in FIG.14, the protrusion 786 defines side grooves 788.

[0095] The sprayer 776 defines a pair of I-shaped openings 800corresponding in location to the location of the protrusions 786 on thecontainer 772. Each I-shaped opening 800 defines a pair of opposingspring tabs 802. As disclosed in U.S. Pat. No. 5,469,993, to Monsanto,the opposing spring tabs 802 are to be resiliently received by the sidegrooves 788 to secure the sprayer 776 to the container 772 duringstorage. The '993 patent discloses that the container is preferably madeby blow molding. As shown in FIG. 14, the protrusions 786 define a firstoverhang 804 extending beyond the inner portion of the recess a distanceD3 and a second overhang 806 extending beyond the outer surface of therecess a distance D4. Unfortunately, this design is undesirable in thatit is very difficult to manufacture the opposing spring tabs 802 of thesprayer 750 and the protrusions 786 of the container 730 to sufficienttolerances that the sprayer can be securely attached to the container730 in this manner. In an effort to avoid having the sprayer detach fromthe container during shipment, sprayers of this design have been gluedto containers or tied to the containers during shipping. Neither ofthese approaches was desirable from an aesthetic, cost or functionalbasis.

[0096] Importantly, however, the assembly 720 of the present inventionovercomes these drawbacks. The positioning of the studs 752 along theseam line 812 of the container 730 permits the studs 752 to bemanufactured with a significantly larger first overhand distance D1 andsecond overhang distance D2. As a result, the studs, in cooperation withthe bayonet openings of the sprayer 750, can secure the sprayer 750securely to the container 730 during shipment.

[0097] The reason that this larger overhang is possible is bestunderstood in connection with FIG. 17 which schematically illustratesthe method of manufacturing a container 730. A first mold half 814 and asecond mold half 816 are positioned on either side of a break plane 818.Plastic is then blown into the mold to form the container 730. Becausethe mold halves separate in a direction perpendicular to the breakplane, the first mold half 814 can define a first flange 820 whichextends beyond the side of the stem 754 a distance approximately equalto D1. Similarly, the second mold half 816 can form a second flange 822which extends beyond a recess a distance approximately equal to D2.

[0098] As shown in FIG. 1d, during shipment the inlet to the internalflow channel 204 of the stem 192 of the handle is blocked by a plug 344mounted within the internal flow channel 206 of the horizontal portion194 of the handle. The plug 344 includes first and second sealingflanges 346 and 348 which prevent the flow of fluid between them and thewall forming the internal flow channel 206. The end of the plug 344facing the open end 210 of the handle 194 defines a cutout 350.

[0099] Importantly, the mating of the upper nipple 162 of the checkvalve 160 with the inlet 124 of the shaft prevents fluid from leakingout the handle during shipment and storage of the assembly 10, prior touse. On the other hand, the plug 344 provides a fail-safe backup in theevent the locking plate 272 is moved to the open position and the handleis raised.

[0100] When it is desired to use the assembly 10 to dispense fluid 260from the container 20, the adaptor 300 on the end of the tubing 222 isinserted into the internal flow channel 206 of the horizontal 194portion of the handle. This causes the inner section 306 of the adaptor300 to push the plug away from the outlet of the internal flow channel206 of the horizontal portion of the handle so that the sealing flanges346 and 348 are pushed beyond the outlet of the internal flow channel204 of the stem 204, as shown in FIG. 1a. The inner section 306 of theadaptor 300 forms a port with the cutout 350 of the plug 344 throughwhich fluid may flow from the internal flow channel 206 of thehorizontal portion 194 of the handle 190 and the interior flow channel309 of the adaptor 300. The locking plate 272 is then moved from thelocked position shown in FIG. 4 to the unlocked position shown in FIG.3. The grip portion 194 of the handle can then be lifted upward asillustrated in FIG. 2. This causes the second O-ring 256 to pressagainst the tapering portion 142 of the body 132 of the piston 130creating a fluid-tight seal. This also causes the fluid 260 to be drawnthrough the check valve 160 into the lower portion 152 of the chamber42. It is not necessary to draw the handle completely upward. On theother hand, to maximize the amount of fluid that may be dispensedwithout repressurizing the container, the handle may be drawn to itsfully pressurized position as illustrated in FIG. 5. In this position,the spring 180 is fully compressed between the coupler 70 and the piston130. The handle 190 is then released, allowing the spring 180 to forcethe piston 130 downward against the fluid 260 in the lower portion 152of the chamber 42. As the check valve 160 prevents fluid from flowingout of the chamber 42 fluid is forced upward through the inlet end 124of the internal flow channel 122 defined by the shaft 110. This fluidflows through the internal flow channel 200 of the stem 192 and theinternal flow channel 206 of the grip portion 194 of the handle 190. Thefluid is likewise forced through the tubing 222 to the spray nozzle 220.Fluid is dispensed from the spray nozzle 220 by depressing the actuator240 operating the release valve (not shown) for the nozzle 220.

[0101] Significantly, the assembly 10 of the present invention permitsthe quick and easy release of pressure within the pump attachment 30.Specifically, as shown in FIGS. 6 and 6a, the handle 190 can be forcedrapidly downward so as to move the second end 114 of the shaft 110downward relative the piston 130. This causes the second O-ring mountedon the radially outward extending portion 118 of the lower end 114 ofthe shaft 110 to move downward away from the tapering portion 142 of theinner annular surface 138. This releases a seal between the shaft 110and the piston 130 and permits fluid 260 to flow through the channel 140between the inner annular surface 138 of the piston 130 and the outersurface of the shaft 110. This fluid 260 is eventually drained from theupper portion 150 of the body 40 of the attachment through a pair ofoutlet openings 346.

[0102] Importantly, the release of pressure from the body 40 of theattachment 30 prevents fluid from inadvertently being released from theassembly 10 during operation, transport and storage of the apparatus.Further, as illustrated in FIG. 7, this release of pressure permits theshaft 110 to return to its fully retracted position so that the mouthportion 202 of the handle can be received within the aperture 74 in thecoupler 70 against the coupler 70 and locked in place against the handleseat by the locking plate of the coupler.

[0103] Those of skill in the art will recognize that this invention maybe embodied in several forms, without departing from the spirit of theinvention, and the foregoing description is therefore intended to beillustrative and not restrictive.

We claim:
 1. A pump attachment for a container defining a neck,comprising: a body defining an elongate chamber having a first end, asecond end and an interior wall extending between said first end andsaid second end; a coupler sized and shaped to secure said body to aneck of a container; a shaft extending through an opening in said firstend of said chamber, said shaft defining an internal flow channel; aone-piece piston reciprocally mounted within said chamber, said pistondefining an inner annular surface surrounding said shaft and an upperouter annular surface sized and shaped to form a sealing engagement withsaid interior wall of said body and a lower outer annular surface sizedand shaped to form a sealing engagement with said interior wall of saidbody, said piston separating said chamber into an upper portion abovesaid piston and a lower portion below said piston; an inlet valve atsaid second end of said body, configured to permit the flow of fluidinto said chamber and restrict the flow of fluid out of said chamber;and a biasing member between said piston and said first end of saidchamber, wherein said attachment further defines a first sealing surfacesubstantially fixed with respect to said piston and a second sealingsurface substantially fixed with respect to said shaft, said firstsealing surface and said second sealing surface having a first positionwherein said first sealing surface and said second sealing surfacecooperate to prevent the flow of liquid between said piston and saidshaft and a second position wherein said first sealing surface and saidsecond sealing surface permit the flow of liquid between said piston andsaid shaft.
 2. The attachment of claim 1, wherein said upper outerannular surface is defined by an upper lip adapted to flex outward inresponse to downward pressure and said lower outer annular surface isdefined by a lower lip adapted to flex outward in response to upwardpressure.
 3. The attachment of claim 2, wherein said piston furthercomprises an inwardly tapered seat, which defines said first sealingsurface.
 4. The attachment of claim 3, wherein said attachment furthercomprises an O-ring mounted on said shaft, which defines said secondsealing surface.
 5. The attachment of claim 5, wherein said attachmentfurther comprises a spray nozzle communicating with said internal flowchannel.
 6. The attachment of claim 5, wherein said attachment furthercomprises an actuator for selectively preventing the flow of fluidthrough said spray nozzle.
 7. The attachment of claim 6, wherein saidattachment further comprises a handle secured to said shaft.
 8. Theattachment of claim 7, wherein said attachment further comprises a latchmovable between a first location wherein said latch generally preventssaid shaft from being drawn through said first end of said body and asecond location wherein said latch generally permits said shaft frombeing drawn through said first end of said body.
 9. The attachment ofclaim 8, wherein said attachment further comprises a spray nozzlecommunicating with said internal flow channel.
 10. A pump attachment fora container defining a neck, comprising: a body defining an elongatechamber having a first end, a second end and an interior wall extendingbetween said first end and said second end; a coupler sized and shapedto secure said body to a neck of a container; a shaft extending throughan opening in said first end of said chamber, said shaft defining aninternal flow channel; a handle integrally formed with said shaft so asto form a single piece; a piston reciprocally mounted within saidchamber, said piston defining an inner annular surface surrounding saidshaft and an outer annular surface sized and shaped to form a sealingengagement with said interior wall of said body, said piston separatingsaid chamber into an upper portion above said piston and a lower portionbelow said piston; an inlet valve at said second end of said body,configured to permit the flow of fluid into said chamber and restrictthe flow of fluid out of said chamber; and a biasing member between saidpiston and said first end of said chamber, wherein said attachmentfurther defines a first sealing surface substantially fixed with respectto said piston and a second sealing surface substantially fixed withrespect to said shaft, said first sealing surface and said secondsealing surface having a first position wherein said first sealingsurface and said second sealing surface cooperate to prevent the flow ofliquid between said piston and said shaft and a second position whereinsaid first sealing surface and said second sealing surface permit theflow of liquid between said piston and said shaft.